A digital filtering method and system

Abstract

The invention discloses a digital filtering method and system, which are used for digital filtering of collected wellhead signals. The method provided by the present invention includes: collecting oilfield wellhead signals; selecting a section of wellhead signals, and judging its change trend; calculating process noise covariance and measurement noise covariance according to the change trend; using the error covariance, process noise covariance, and Noise covariance, filtering output value, measurement noise covariance and current wellhead signal to obtain the current filtering output value and error covariance; according to the filtering output value and error covariance, set the parameters of the digital filtering algorithm to perform digital filtering . In the present invention, by judging the change trend of the wellhead signal, obtaining the process noise covariance and measurement noise covariance, and then controlling the digital filtering, not only can accurately filter the collected signal, reduce interference, but also reduce the amount of calculation, improve The filtering speed ensures fast and accurate acquisition of wellhead data.

Description

technical field [0001] The present invention relates to the field of signal processing, in particular to a digital filtering method and system Background technique [0002] As an important energy source in modern society, petroleum is accompanied by the huge demand of human society. Standardized and process-based mining is particularly important. If a large number of single wells are extracted only by manual well patrolling, the efficiency will be very low, which requires automation. data collection. However, the data obtained by automatic collection is easily distorted by noise interference, so it is necessary to digitally filter the collected data signal. [0003] Now commonly used digital filtering methods such as limiting filtering, median filtering, arithmetic mean filtering, weighted mean filtering and low-pass filtering, etc. Among them, limiting filtering, median filtering and other methods have poor filtering effects and low accuracy, while arithmetic mean filterin...

AI Technical Summary

Problems solved by technology

[0002] As an important energy substance in modern society, petroleum is accompanied by the huge demand of human society. Standardized and process-based mining is particularly important. If a large number of single wells are extracted only by manual well patrolling, the efficiency will be very low, which requires automation. data collection

However, the data obtained by automatic collection is easily distorted by noise interference, so it is necessary to digitally filter the collected data signal

[0003] Now commonly used digital filtering methods such as limiting filtering, median filtering, arithmetic mean filtering, weighted mean filtering and low-pass filtering, etc. Among them, limiting filtering, median filtering and other methods have poor filtering effects and low accuracy, while arithmetic mean filtering Filtering, moving average filtering, weighted average filtering, and low-pass filtering have high precision, but the amount of calculation is large, resulting in poor real-time performance

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